1. Field of the Disclosure
This specification relates to a polarized glasses type stereoscopic image display device and a method of fabricating the same, and particularly, to a polarized glasses type image display device, capable of viewing a stereoscopic image using polarized glasses, and a method of fabricating the same.
2. Background of the Disclosure
Briefly, a three-dimensional (3D) display may be referred to as “a system of artificially reproducing a 3D screen.”
Here, the system includes both a software technology by which images are displayed in a 3D form and hardware which actually realizes contents created by the software technology into the 3D form. The reason for including the software technology is that 3D display hardware require that content be generated using different software technology for each method of creating stereoscopic images (stereoscopic image creating method).
Also, a virtual 3D display is a general type of system, which provides a virtual stereoscopic feeling from flat display hardware using a binocular disparity, which is caused as eyes are apart from each other by about 65 mm in a horizontal direction, as one of factors that a user feels a sense of three-dimension. In other words, two eyes see slightly different images (namely, slightly sharing left and right special information with each other) due to the binocular disparity, even if the eyes view the same thing. When the two images are transferred to the brain through the retina, the brain may accurately unify the two images such that the user can feel the sense of three-dimension. This mechanism is employed in a 2D display device in such a manner of simultaneously displaying two left and right images and delivering the two images to the respective eyes so as to create a virtual stereoscopic feeling, which is the virtual 3D display.
In order to show images of two channels on one screen in the virtual 3D display hardware device, for example, channels are output one by one on one screen in such a manner of switching lines one by one in a right or left direction. For an auto-stereoscopic display device, in view of a hardware configuration, when the images of two channels are simultaneously output on one display device, a right image may be delivered directly to a right eye and a left image may be delivered only to a left eye. Also, for a glasses-wearing type display device, a right image is hidden from a left eye and a left image is hidden from a right eye by use of specific glasses suitable for each stereoscopic image creating method.
The glasses-wearing methods may include an anaglyph type of wearing blue and red glasses on left and right eyes, respectively, a polarized glasses type of wearing polarized glasses with different right and left polarization directions, and a liquid crystal shutter type using glasses with a liquid crystal shutter, which synchronizes with a period of repeating a time-divided screen. Among others, the polarized glasses type has an advantage of easily realizing 3D images from two images configured in a 2D form.
FIG. 1 is an exemplary view illustrating a schematic structure of a general polarized glasses type stereoscopic image display device.
Referring to FIG. 1, a polarized glasses type is a type of spatially isolating left and right images from each other by arranging a patterned retarder 2 on a front surface of an image panel 1.
The pattern retarder 2 of the polarized glasses type stereoscopic image display device refers to a film which has a predetermined pattern on the position basis, such that polarized states of left and right images can be perpendicular to each other.
For example, the patterned retarder 2 may include a glass substrate. Although not shown in detail, an alignment layer and a double refraction layer may be sequentially formed on the substrate. The alignment layer and the double refraction layer may have regular patterns of first and second regions 2a and 2b. The first region 2a and the second region 2b may be formed by stripes which are arranged in an alternating manner to correspond to image lines of the image panel 1. The regions 2a and 2b may have the same alignment direction.
Here, when the image panel 1 is implemented as a liquid crystal display device, a polarizer 11 having an optical absorption shaft in a horizontal direction may be disposed, for example, between the image panel 1 and the patterned retarder 2.
FIG. 2 is a planar view schematically illustrating a partial structure of a general liquid crystal display (LCD) device, which merely illustrates a part of upper and lower glass substrates for the sake of brief explanation.
Here, the LCD device actually has N×M pixels defined by intersection between N gate lines and M data lines. However, for brief description, one pixel composed of red, green and blue (R, B, B) sub-pixels is exemplarily illustrated.
For reference, a reference numeral Ps denotes one sub-pixel region.
FIG. 3 schematically illustrates a cross-section taken along the line A-A′ of FIG. 2.
Referring to FIGS. 2 and 3, the LCD device may include two sheets of glass substrates 5 and 10, and a liquid crystal layer (not shown) interposed therebetween with a cell gap maintained by a column spacer 40.
On the lower glass substrate 10 may be formed gate lines 16 and data lines 17 which are arranged horizontally and longitudinally to define sub-pixel regions Ps. A thin film transistor (TFT) as a switching device may be formed on each intersection between the gate lines 16 and the data lines 17.
Although not shown, a plurality of pixel electrodes and common electrodes for forming a horizontal electric field may be formed within the sub-pixel region Ps in an alternating manner. A common line 81 may be arranged in substantially the same direction as the gate line 16 below the sub-pixel region Ps.
The TFT may include a gate electrode connected to the gate line 16, a source electrode connected to the data line 17, and a drain electrode connected to the pixel electrode. TFT may also include a plurality of insulating layers 15a, 15b and 15c for insulation between components, and an active pattern forming a conductive channel between the source electrode and the drain electrode by a gate voltage supplied to the gate electrode.
The upper glass substrate 5 may be provided with a color filter array. The color filter array may include a black matrix 6, color filters 7 (7a, 7b and 7c), and an overcoated layer 9.
In the general polarized glasses type stereoscopic image display device, a currently widely employed method is to arrange left and right images on the line basis. That is, as illustrated, a left image (L) may be arranged on an odd line and a right image (R) on an even line in a perpendicular direction. When the L and R images are displayed on the image panel 1, a viewer may wear watching glasses 3 to watch the L and R images in an isolating manner, thereby enjoying a 3D image.
However, the polarized glasses type may be unable to accurately isolate the L and R images from each other by use of the polarizer because the L and R images come in contact with each other. This may cause a crosstalk that the R image leaks into the left eye and the L image leaks into a right eye, or a limited up/down viewing angle.